History and culture
﻿Three tribes make up the CTUIR: Cayuse, Umatilla and Walla Walla. They have lived on the Columbia River Plateau for over 10,000 years, an area of about 6.4 million acres in what is now northeastern Oregon and southeastern Washington. In 1855, the tribes and the United States government negotiated a treaty in which the tribes ceded 6.4 million acres of land in exchange for reservation land. The CTUIR reserved rights in the treaty, including fishing and hunting rights and the right to gather traditional foods and medicines on public lands within the ceded areas.

The traditional religion of the tribes is called “Washat” or “Seven Drums.” Native languages are still spoken by some, and a language preservation program is helping to reestablish the languages.